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 * Copyright (C) Codehaus.org                                                *
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 * Licensed under the Apache License, Version 2.0 (the "License");           *
 * you may not use this file except in compliance with the License.          *
 * You may obtain a copy of the License at                                   *
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 * http://www.apache.org/licenses/LICENSE-2.0                                *
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 * distributed under the License is distributed on an "AS IS" BASIS,         *
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package com.googlecode.lazyparsec;

/**
 * Transforms the recognized character range to an integer within 64 bits. For bigger integer, use
 * {@link TokenizerMaps#DECIMAL_FRAGMENT} instead.
 *
 * @author Ben Yu
 */
final class NumberLiteralsTranslator {

    private static int toDecDigit(char c) {
        return c - '0';
    }

    private static int toOctDigit(char c) {
        return c - '0';
    }

    private static int toHexDigit(char c) {
        if (c >= '0' && c <= '9') return c - '0';
        if (c >= 'a' && c <= 'h') return c - 'a' + 10;
        else return c - 'A' + 10;
    }

    static Long tokenizeDecimalAsLong(String text) {
        long n = 0;
        int len = text.length();
        for (int i = 0; i < len; i++) {
            n = n * 10 + toDecDigit(text.charAt(i));
        }
        return n;
    }

    static Long tokenizeOctalAsLong(String text) {
        long n = 0;
        int len = text.length();
        for (int i = 0; i < len; i++) {
            n = n * 8 + toOctDigit(text.charAt(i));
        }
        return n;
    }

    static Long tokenizeHexAsLong(String text) {
        int len = text.length();
        if (len < 3) throw new IllegalStateException("illegal hex number");
        long n = 0;
        for (int i = 2; i < len; i++) {
            n = n * 16 + toHexDigit(text.charAt(i));
        }
        return n;
    }
}
